Go to "My Controls" (the same place you get your PMs) now look top left of that screen. There will be two options under "Invision Gallery" called "Your Albums"
and "Your Favorites".
Click "Your Albums", now click the link to create your first album.
With an album create you can then either select it in your control panel, and then upload images to it (using the "select operation" pull down box), or you can view your new album and click the "new image" button to upload photos.
At the moment all uploads online are resized to 800x600 maximum. But that will change as the software that runs the gallery side of things is improved.
Enjoy
